| 摘要 |
PURPOSE:To prolong the life of an element by setting the transformation temperature and heating/cooling temperature of the energy conversion element made of a profile memory alloy so that both heating and cooling temperature are kept equal to or more than the martensite reverse transformation temperature. CONSTITUTION:Both cooling and heating sides of an energy conversion element made of a profile memory alloy of a heat driven engine are kept at or above the martensite reverse transformation completing temperature Af, thereby only an austenite phase (host phase) d and a stress inducing martensite phase c appear along the driving cycle and a heat elastic martensite phase (a) due to cooling does not appear. Accordingly, the matching disturbance due to a unistrain change from d to (a) during a temperature drop is made small, and only transformations between d and c occur during the deformation or profile recovery process (uni-stress process) of the element, thus the matching disturbance is made small and the life of the element can be prolonged. |
